This invention relates an internal combustion engine having push rod operated overhead valves and more particularly to a push rod cover for such engine.
In many instances, it is desirable to employ push rod operated rather than directly operated overhead valves. Where this is done, the valve is operated through a rocker arm from a remotely positioned camshaft by means of a push rod and at times a tappet that actuates the push rod. With this type of mechanism, it is desirable to provide an arrangement wherein the actuating mechanism that interconnects the camshaft to the rocker arm can be conveniently accessed. Normally, however, the push rods are disposed in such an orientation that each must be accessed separately.
It is, therefore, a principal object of this invention to provide an improved engine construction wherein a plurality of push rods that operate respective rocker arms are disposed so that they all lie within a common cavity and that this cavity can be accessed through removal of a cover that will afford access to the push rods and, if desired, the associated tappets.
It is, therefore, a still further object of this invention to provide an improved, simple and yet accessible engine construction for engines embodying push rod operated overhead valves.
The problems aforenoted are particularly acute in conjunction with engines which are air cooled. As is well known, the external surface of major engine body components of air cooled engines are formed with a plurality of outwardly extending cooling fins. If the engine valves are push rod operated, this finning of the outer body components may make it difficult to access the push rods for servicing.
Therefore, many engines that are air cooled and are provided with push rod operated valves position the push rods externally of the engine body. Then in order to protect the push rods and improve the appearance, they are contained within individual, externally positioned tubes. This not only increases the size and cost of the engine, but also makes it less attractive in appearance and more prone to potential damage, particularly with application in vehicles where the engine is exposed, such as motorcycles.
It is, therefore, a still further object of this invention to provide an improved engine construction for a push rod operated internal combustion engine as utilized in powering a vehicle such as a motorcycle.